Devre PIC16C622 mikrodenetleyicisi üzerine kurulu 1Ω 999Ω arası direnç ölçümü 1nF 999 nF arası kapasitör ölçümü yapılabiliryor bilgisayar bağlantısı bulunuyor denetleyici yazılımı assembly ile pc yazılımı Visual Basic ile hazırlanmış. PIC16C622 ve uygulama devresi hakkında tüm detaylar formüller verilmiş orjinal microchip uygulama notudur.
Devre şeması;
The application circuit, called PICMETER, uses a PIC16C622 as a resistance and capacitance meter. The PICMETER uses a variation of the single-slope integrating converter. The linear slope and integrator of Figure 13 are replaced with the exponential charge waveform of an RC. The charge time of a known component is compared against the charge time of an unknown component to determine the value of the unknown component.
A schematic of the PICMETER is shown in Figure 16. All reference designators cited in this section refer to this schematic. Results are transmitted to a PC which displays the value measured.
TITLE "PICMETER Firmware for PIC16C622"
LIST P = 16C622, F = INHX8M
INCLUDE "C:\PICMASTR\P16CXX.INC"
__FUSES _BODEN_OFF&_CP_OFF&_PWDT_ON&_WDT_OFF&_XT_OSC
;****************************************************************************
;*--------------------------------------------------------------------------*
;*- -*
;*- PICMETER - Resistance and Capacitance Meter -*
;*- -*
;*--------------------------------------------------------------------------*
;*- -*
;*- Author: Rodger Richey -*
;*- Applications Engineer -*
;*- Filename: picmeter.asm -*
;*- Revision: 1 May 1995 -*
;*- -*
;*--------------------------------------------------------------------------*
;*- -*
;*- PICMETER is based on a PIC16C622 which has two comparators and a -*
;*- variable voltage reference. Resistance and capacitance is -*
;*- calculated by measuring the time constant of a RC network. The -*
;*- toggle switch selects either resistor or capacitor input. The -*
;*- pushbutton switch starts a measurement. The time constant of the -*
;*- unknown component is compared to that of known component to -*
;*- calculate the value of the unknown component. The following -*
;*- formulas are used: -*
;*- -*
;*- Resistance: Ru = ( Rk * Tu ) / Tk -*
;*- Capacitance: Cu = ( Ck * Tu ) / Tk -*
;*- -*
;*--------------------------------------------------------------------------*
;****************************************************************************
;****************************************************************************
;*--------------------------------------------------------------------------*
;*- RS232 code borrowed from Application Note AN593 -*
;*- "Serial Port Routines Without Using the RTCC" -*
;*- Author: Stan D'Souza -*
;*--------------------------------------------------------------------------*
;****************************************************************************
xtal equ .4000000
baud equ .9600
fclk equ xtal/4
;****************************************************************************
;The value baudconst must be a 8-bit value only
baudconst equ ((fclk/baud)/3-2)
;****************************************************************************
;****************************************************************************
; Bit Equates
;****************************************************************************
BEGIN equ 0 ;begin a measurement flag
DONE equ 7 ;done measuring flag
WHICH equ 5 ;R or C measurement flag
F_ERROR equ 3 ;error detection flag
EMPTY equ 5 ;flag if component is connected
V0 equ 0 ;power for R reference ckt
V1 equ 1 ;power for C reference ckt
V2 equ 2 ;ground for C reference ckt
V3 equ 3 ;power for unknown R ckt
V4 equ 4 ;ground for unknown C ckt
msb_bit equ 7 ;define for bit 7
lsb_bit equ 0 ;define for bit 0
RkHI equ 0x07 ;value of the known resistance, R4, in ohms
RkMID equ 0x9D ;measured by a Fluke meter
RkLO equ 0x38
CkHI equ 0x07 ;value of the known capacitance, C1, in pF
CkMID equ 0x47 ;measured by a Fluke meter
CkLO equ 0x48
;****************************************************************************
; User Registers
;****************************************************************************
; Bank 0
W_TEMP equ 0x20 ;Bank 0 temporary storage for W reg
STATUS_TEMP equ 0x21 ;temporary storage for STATUS reg
Ttemp equ 0x23 ;temporary Time register
flags equ 0x24 ;flags register
count equ 0x25 ;RS232 register
txreg equ 0x26 ;RS232 data register
delay equ 0x27 ;RS232 delay register
offset equ 0x28 ;table position register
msb equ 0x29 ;general delay register
lsb equ 0x2A ;general delay register
TimeLO equ 0x40 ;Time registers
TimeMID equ 0x41
TimeHI equ 0x42
; Math related registers
ACCaHI equ 0x50 ;24-Bit accumulator a
ACCaMID equ 0x51
ACCaLO equ 0x52
ACCbHI equ 0x53 ;24-Bit accumulator b
ACCbMID equ 0x54
ACCbLO equ 0x55
ACCcHI equ 0x56 ;24-Bit accumulator c
ACCcMID equ 0x57
ACCcLO equ 0x58
ACCdHI equ 0x59 ;24-Bit accumulator d
ACCdMID equ 0x5A
ACCdLO equ 0x5B
temp equ 0x5C ;temporary storage
; User Registers Bank 1
;W_TEMP equ 0xA0 ;Bank 1 temporary storage for W reg
; User defines
#define tx PORTB,7 ;define for RS232 TXD output pin
;****************************************************************************
org 0x0
goto init
org 0x4
goto ServiceInterrupts
org 0x10
init
bcf STATUS,RP0 ;select bank 0
clrf PORTA ;clear PORTA and PORTB
clrf PORTB
bsf tx ;set TXD output pin
clrf flags ;clear flags register
movlw 0x10 ;load table offset register
movwf offset
clrf INTCON ;clear interrupt flags and disable interrupts
movlw 0x07 ;turn off comparators, mode 111
movwf CMCON
call delay20 ;wait for comarators to settle
movf CMCON,F
bcf PIR1,CMIF
bsf STATUS,RP0 ;select bank 1
movlw 0x88 ;WDT prescalar,internal TMR0 increment
movwf OPTION_REG
clrf TRISA ;PORTA all outputs, discharges RC ckts
movlw 0x60 ;PORTA<7,4:0> outputs, PORTA<6:5> inputs
movwf TRISB
movlw 0x0C ;setup Voltage Reference
movwf VRCON
bcf STATUS,RP0 ;select bank 0
movlw 0x08 ;enable RBIE interrupt
movwf INTCON
call vlong ;delay before transmitting boot message
call vlong ;to allow computer program to setup
call vlong
call BootMSG ;transmit boot message
bsf INTCON,GIE ;enable global interrupt bit
start
btfss flags,BEGIN ;wait for a start measurement key press
goto start
bcf flags,BEGIN ;clear start measurement flag
bcf INTCON,GIE ;transmit a start measurement message
movlw 'S' ;to the PC
call Send
bsf INTCON,GIE
clrf TimeHI ;reset Time registers
clrf TimeMID
clrf TimeLO
btfss PORTB,WHICH ;detect if resistor or capacitor measure
goto Capacitor
Resistor
bsf STATUS,RP0 ;set V0 to input
bsf TRISB,V0
bcf STATUS,RP0
call AnalogOn ;turn analog on
clrf TMR0
nop
bsf PORTB,V3 ;turn power on to unknown RC ckt
RwaitU btfsc flags,F_ERROR ;detect if an error occurs
goto ErrorDetect
btfss flags,DONE ;measurement completed flag
goto RwaitU
bcf flags,DONE ;clear measurement completed flag
call AnalogOff ;turn analog off
call SwapTtoA ;swap Time to accumulator a
movlw RkHI ;swap known resistance value
movwf ACCbHI ;to accumulator b
movlw RkMID
movwf ACCbMID
movlw RkLO
movwf ACCbLO
call Mpy24 ;multiply accumulator a and b
bsf STATUS,RP0 ;set V3 to input
bsf TRISB,V3
bcf STATUS,RP0
call AnalogOn ;turn analog on
clrf TMR0
nop
bsf PORTB,V0 ;turn power on to known RC ckt
RwaitK btfsc flags,F_ERROR ;detect if an error occurs
goto ErrorDetect
btfss flags,DONE ;measurement completed flag
goto RwaitK
bcf flags,DONE ;clear measurement completed flag
call AnalogOff ;turn analog off
call SwapTtoA ;swap Time to accumulator a
call Div24 ;divide multiply by known time
bcf INTCON,GIE ;disable all interrupts
movlw 'R' ;transmit, for R measurement
call Send
bsf INTCON,GIE ;enable global interrupt bit
goto start ;restart
Capacitor
bsf STATUS,RP0 ;set V2 to input
bsf TRISB,V2
bcf STATUS,RP0
call AnalogOn ;turn analog on
clrf TMR0
nop
bsf PORTB,V1 ;turn power on to unknown RC ckt
CwaitU btfsc flags,F_ERROR ;detect if an error occurs
goto ErrorDetect
btfss flags,DONE ;measurement completed flag
goto CwaitU
bcf flags,DONE ;clear measurement completed flag
call AnalogOff ;turn analog off
call SwapTtoA ;swap Time to accumulator a
movlw CkHI ;swap known resistance value
movwf ACCbHI ;to accumulator b
movlw CkMID
movwf ACCbMID
movlw CkLO
movwf ACCbLO
call Mpy24 ;multiply accumulator a and b
bsf STATUS,RP0 ;set V3 to input
bsf TRISB,V4
bcf STATUS,RP0
call AnalogOn ;turn analog on
clrf TMR0
nop
bsf PORTB,V1 ;turn power on to known RC ckt
CwaitK btfsc flags,F_ERROR ;detect if an error occurs
goto ErrorDetect
btfss flags,DONE ;measurement completed flag
goto CwaitK
bcf flags,DONE ;clear measurement completed flag
call AnalogOff ;turn analog off
call SwapTtoA ;swap Time to accumulator a
call Div24 ;divide multiply by known time
bcf INTCON,GIE ;disable all interrupts
movlw 'C' ;transmit, for C measurement
call Send
bsf INTCON,GIE ;enable global interrupt bit
goto start ;restart
ErrorDetect
bcf STATUS,RP0 ;disable TMR0
bcf INTCON,T0IE
bcf INTCON,T0IF
call AnalogOff ;turn analog off
bcf flags,F_ERROR ;clear error flag
bcf INTCON,GIE ;disable all interrupts
movlw 'E' ;transmit, for C measurement
call Send
bsf INTCON,GIE ;enable global interrupt bit
goto start ;restart
;****************************************************************************
;*--------------------------------------------------------------------------*
;*- RS232 Transmit Routine -*
;*- Borrowed from AN593, "Serial Port Routines Without Using the RTCC" -*
;*- Author: Stan D'Souza -*
;*- This is the routine that interfaces directly to the hardware -*
;*--------------------------------------------------------------------------*
;****************************************************************************
Transmit
bcf STATUS,RP0
movwf txreg
bcf tx ;send start bit
movlw baudconst
movwf delay
movlw 0x9
movwf count
txbaudwait
decfsz delay
goto txbaudwait
movlw baudconst
movwf delay
decfsz count
goto SendNextBit
movlw 0x9
movwf count
bsf tx ;send stop bit
return
SendNextBit
rrf txreg
btfss STATUS,C
goto Setlo
bsf tx
goto txbaudwait
Setlo bcf tx
goto txbaudwait
;____________________________________________________________________________
;****************************************************************************
;*--------------------------------------------------------------------------*
;*- Generic Transmit Routine -*
;*- Sends what is currently in the W register and accumulator ACCc -*
;*--------------------------------------------------------------------------*
;****************************************************************************
Send
call Transmit
call delay1 ;delay between bytes
movf ACCcHI,W ;transmit high resistance byte
call Transmit
call delay1 ;delay between bytes
movf ACCcMID,W ;transmit mid resistance byte
call Transmit
call delay1 ;delay between bytes
movf ACCcLO,W ;transmit low resistance byte
call Transmit
call delay1 ;delay between bytes
return
;____________________________________________________________________________
;****************************************************************************
;*--------------------------------------------------------------------------*
;*- Interrupt Service Routines -*
;*--------------------------------------------------------------------------*
;****************************************************************************
ServiceInterrupts
movwf W_TEMP ;Pseudo push instructions
swapf STATUS,W
bcf STATUS,RP0
movwf STATUS_TEMP
movf TMR0,W
movwf Ttemp
btfsc INTCON,T0IF ;Service Timer 0 overflow
call ServiceTimer
btfsc PIR1,CMIF ;Stops Timer0, Records Value
call ServiceComparator
btfsc INTCON,RBIF ;Service pushbutton switch
call ServiceKeystroke ;Starts a measurement
bcf STATUS,RP0
swapf STATUS_TEMP,W ;Pseudo pop instructions
movwf STATUS
swapf W_TEMP,F
swapf W_TEMP,W
retfie
;____________________________________________________________________________
;****************************************************************************
;*--------------------------------------------------------------------------*
;*- Borrowed from AN552, "Implementing Wake-up on Key Stroke" -*
;*- Author: Stan D'Souza -*
;*--------------------------------------------------------------------------*
;****************************************************************************
ServiceKeystroke
bcf INTCON,RBIE ;disable interrupt
comf PORTB,W ;read PORTB
bcf INTCON,RBIF ;clear interrupt flag
andlw B'01000000'
btfsc STATUS,Z
goto NotSwitch
call delay16 ;de-bounce switch for 16msec
comf PORTB,W ;read PORTB again
call KeyRelease ;check for key release
bsf flags,BEGIN
return
NotSwitch ;detected other PORTB pin change
bcf INTCON,RBIF ;reset RBI interrupt
bsf INTCON,RBIE
return
KeyRelease
call delay16 ;debounce switch
comf PORTB,W ;read PORTB
bcf INTCON,RBIF ;clear flag
bsf INTCON,RBIE ;enable interrupt
andlw B'01000000'
btfsc STATUS,Z ;key still pressed?
return ;if no, then return
sleep ;else, save power
bcf INTCON,RBIE ;disable interrupts
comf PORTB,W ;read PORTB
bcf INTCON,RBIF ;clear flag
goto KeyRelease ;try again
;____________________________________________________________________________
;****************************************************************************
;*--------------------------------------------------------------------------*
;*- ISR to service a Timer0 overflow -*
;*--------------------------------------------------------------------------*
;****************************************************************************
ServiceTimer
incf TimeMID,F ;increment middle Time byte
btfsc STATUS,Z ;if middle overflows,
incf TimeHI,F ;increment high Time byte
btfsc TimeHI,EMPTY ;check if component is connected
bsf flags,F_ERROR ;set error flag
bcf INTCON,T0IF ;clear TMR0 interrupt flag
return
;____________________________________________________________________________
;****************************************************************************
;*--------------------------------------------------------------------------*
;*- ISR to service a Comparator interrupt -*
;*--------------------------------------------------------------------------*
;****************************************************************************
ServiceComparator
bcf STATUS,RP0 ;select bank 0
btfss PORTB,WHICH ;detect which measurement, R or C?
goto capcomp
btfss CMCON,C1OUT ;detect if R ckt has interrupted
goto scstop
goto scend
capcomp
btfsc CMCON,C2OUT ;detect if C ckt has interrupted
goto scend
scstop
bcf INTCON,T0IE ;disable TMR0 interrupts
bcf INTCON,T0IF
movf Ttemp,W
movwf TimeLO
bsf flags,DONE ;set DONE flag
scend
bcf PIR1,CMIF ;clear comparator interrupt flag
return
;____________________________________________________________________________
;****************************************************************************
;*--------------------------------------------------------------------------*
;*- Turn Comparators and Vref On -*
;*--------------------------------------------------------------------------*
;****************************************************************************
AnalogOn
bcf STATUS,RP0 ;select bank 0
movlw 0x02 ;turn comparators on, mode 010
movwf CMCON ;4 inputs multiplexed to 2 comparators
bsf STATUS,RP0 ;select bank 1
movlw 0x0F ;make PORTA<3:0> all inputs
movwf TRISA
bsf VRCON,VREN
bcf STATUS,RP0 ;select bank 0
call delay20 ;20msec delay
movf CMCON,F ;clear comparator mismatch condition
bcf PIR1,CMIF ;clear comparator interrupt flag
bsf STATUS,RP0
bsf PIE1,CMIE ;enable comparator interrupts
bcf STATUS,RP0
bsf INTCON,PEIE ;enable peripheral interrupts
bcf flags,F_ERROR
clrf TMR0 ;clear TMR0 counter
nop
nop
bcf INTCON,T0IF ;clear TMR0 interrupt flag
bsf INTCON,T0IE ;enable TMR0 interrupts
return
;____________________________________________________________________________
;****************************************************************************
;*--------------------------------------------------------------------------*
;*- Turn Comparators and Vref Off -*
;*--------------------------------------------------------------------------*
;****************************************************************************
AnalogOff
bcf STATUS,RP0
bcf INTCON,PEIE
movlw 0x80 ;reset PORTB value
movwf PORTB
bsf STATUS,RP0 ;select bank 1
bcf PIE1,CMIE ;disable comparator interrupts
clrf TRISA ;set PORTA pins to outputs, discharge RC ckt
movlw 0x60 ;set PORTB 7,4-0 as outputs, 6,5 as inputs
movwf TRISB
bcf VRCON,VREN ;disable Vref
bcf STATUS,RP0 ;select bank 0
movlw 0x07
movwf CMCON ;disable comparators
call delay20 ;20msec delay
movf CMCON,F ;clear comparator mismatch condition
bcf PIR1,CMIF ;clear comparator interrupt flag
bcf INTCON,T0IF ;clear Timer0 interrupt flag
call vlong ;long delay to allow capacitors to discharge
call vlong
call vlong
return
;____________________________________________________________________________
;****************************************************************************
;*--------------------------------------------------------------------------*
;*- Swap Time to Accumulator a -*
;*--------------------------------------------------------------------------*
;****************************************************************************
SwapTtoA
bcf STATUS,RP0
movf TimeHI,W
movwf ACCaHI
movf TimeMID,W
movwf ACCaMID
movf TimeLO,W
movwf ACCaLO
clrf TimeHI
clrf TimeMID
clrf TimeLO
return
;____________________________________________________________________________
;****************************************************************************
;*--------------------------------------------------------------------------*
;*- Transmit the Boot Message -*
;*--------------------------------------------------------------------------*
;****************************************************************************
BootMSG
bcf STATUS,RP0 ;select bank 0
msg movlw HIGH Table ;init the PCH for a table call
movwf PCLATH
movf offset,W ;move table offset into W
call Table ;get table value
call Transmit ;transmit table value
call delay1 ;delay between bytes
decfsz offset,F ;check for end of table
goto msg
movlw 0x10 ;reset table offset
movwf offset
return
;____________________________________________________________________________
;****************************************************************************
;*--------------------------------------------------------------------------*
;*- Delay Routines -*
;*--------------------------------------------------------------------------*
;****************************************************************************
vlong movlw 0xff ;very long delay, approx 200msec
movwf msb
goto d1
delay20 ;20 msec delay
movlw .26
movwf msb
goto d1
delay16 ;16 msec delay
movlw .21
movwf msb
goto d1
delay1 ;approx 750nsec delay
movlw .1
movwf msb
d1 movlw 0xff
movwf lsb
d2 decfsz lsb,F
goto d2
decfsz msb,F
goto d1
return
;____________________________________________________________________________
org 0x200
;****************************************************************************
;*--------------------------------------------------------------------------*
;*- Table for Boot Message -*
;*--------------------------------------------------------------------------*
;****************************************************************************
Table ;boot message "PICMETER Booted!"
addwf PCL ;add W to PCL
retlw 0
retlw '!'
retlw 'd'
retlw 'e'
retlw 't'
retlw 'o'
retlw 'o'
retlw 'B'
retlw ' '
retlw 'R'
retlw 'E'
retlw 'T'
retlw 'E'
retlw 'M'
retlw 'C'
retlw 'I'
retlw 'P'
;____________________________________________________________________________
;****************************************************************************
;*--------------------------------------------------------------------------*
;*- 24-bit Addition -*
;*- -*
;*- Uses ACCa and ACCb -*
;*- -*
;*- ACCa + ACCb -> ACCb -*
;*--------------------------------------------------------------------------*
;****************************************************************************
Add24
movf ACCaLO,W
addwf ACCbLO ;add low bytes
btfsc STATUS,C ;add in carry if necessary
goto A2
A1 movf ACCaMID,W
addwf ACCbMID ;add mid bytes
btfsc STATUS,C ;add in carry if necessary
incf ACCbHI
movf ACCaHI,W
addwf ACCbHI ;add high bytes
retlw 0
A2 incf ACCbMID
btfsc STATUS,Z
incf ACCbHI
goto A1
;____________________________________________________________________________
;****************************************************************************
;*--------------------------------------------------------------------------*
;*- Subtraction ( 24 - 24 -> 24 ) -*
;*- -*
;*- Uses ACCa, ACCb, ACCd -*
;*- -*
;*- ACCa -> ACCd, -*
;*- 2's complement ACCa, -*
;*- call Add24 ( ACCa + ACCb -> ACCb ), -*
;*- ACCd -> ACCa -*
;*--------------------------------------------------------------------------*
;****************************************************************************
Sub24
movf ACCaHI,W ;Transfer ACCa to ACCd
movwf ACCdHI
movf ACCaMID,W
movwf ACCdMID
movf ACCaLO,W
movwf ACCdLO
call compA ;2's complement ACCa
call Add24 ;Add ACCa to ACCb
movf ACCdHI,W ;Transfer ACCd to ACCa
movwf ACCaHI
movf ACCdMID,W
movwf ACCaMID
movf ACCdLO,W
movwf ACCaLO
retlw 0
;____________________________________________________________________________
;****************************************************************************
;*--------------------------------------------------------------------------*
;*- Multiply ( 24 X 24 -> 56 ) -*
;*- -*
;*- Uses ACCa, ACCb, ACCc, ACCd -*
;*- -*
;*- ACCa * ACCb -> ACCb,ACCc 56-bit output -*
;*- with ACCb (ACCbHI,ACCbMID,ACCbLO) with 24 msb's and -*
;*- ACCc (ACCcHI,ACCcMID,ACCcLO) with 24 lsb's -*
;*--------------------------------------------------------------------------*
;****************************************************************************
Mpy24
call Msetup
mloop rrf ACCdHI ;rotate d right
rrf ACCdMID
rrf ACCdLO
btfsc STATUS,C ;need to add?
call Add24
rrf ACCbHI
rrf ACCbMID
rrf ACCbLO
rrf ACCcHI
rrf ACCcMID
rrf ACCcLO
decfsz temp ;loop until all bits checked
goto mloop
retlw 0
Msetup
movlw 0x18 ;for 24 bit shifts
movwf temp
movf ACCbHI,W ;move ACCb to ACCd
movwf ACCdHI
movf ACCbMID,W
movwf ACCdMID
movf ACCbLO,W
movwf ACCdLO
clrf ACCbHI
clrf ACCbMID
clrf ACCbLO
retlw 0
;____________________________________________________________________________
;****************************************************************************
;*--------------------------------------------------------------------------*
;*- Division ( 56 / 24 -> 24 ) -*
;*- -*
;*- Uses ACCa, ACCb, ACCc, ACCd -*
;*- -*
;*- 56-bit dividend in ACCb,ACCc ( ACCb has msb's and ACCc has lsb's) -*
;*- 24-bit divisor in ACCa -*
;*- quotient is stored in ACCc -*
;*- remainder is stored in ACCb -*
;*--------------------------------------------------------------------------*
;****************************************************************************
Div24
call Dsetup
dloop bcf STATUS,C
rlf ACCcLO ;Rotate dividend left 1 bit position
rlf ACCcMID
rlf ACCcHI
rlf ACCbLO
rlf ACCbMID
rlf ACCbHI
btfsc STATUS,C ;invert carry and exclusive or with the
goto clear ;msb of the divisor then move this bit
btfss ACCaHI,msb_bit ;into the lsb of the dividend
incf ACCcLO
goto cont
clear btfsc ACCaHI,msb_bit
incf ACCcLO
cont btfsc ACCcLO,lsb_bit ;check the lsb of the dividend
goto minus
call Add24 ;if = 0, then add divisor to upper 24 bits
goto check ;of dividend
minus call Sub24 ;if = 1, then subtract divisor from upper
;24 bits of dividend
check decfsz temp,f ;do 24 times
goto dloop
bcf STATUS,C
rlf ACCcLO ;shift lower 24 bits of dividend 1 bit
rlf ACCcMID ;position left
rlf ACCcHI
btfsc ACCbHI,msb_bit ;exlusive or the inverse of the msb of the
goto w1 ;dividend with the msb of the divisor
btfss ACCaHI,msb_bit ;store in the lsb of the dividend
incf ACCcLO
goto wzd
w1 btfsc ACCaHI,msb_bit
incf ACCcLO
wzd btfss ACCbHI,msb_bit ;if the msb of the remainder is set and
goto wend
btfsc ACCaHI,msb_bit ;the msb of the divisor is not
goto wend
call Add24 ;add the divisor to the remainder to correct
;for zero partial remainder
wend retlw 0 ;quotient in 24 lsb's of dividend
;remainder in 24 msb's of dividend
Dsetup
movlw 0x18 ;loop 24 times
movwf temp
retlw 0
;____________________________________________________________________________
;****************************************************************************
;*--------------------------------------------------------------------------*
;*- 2's Complement -*
;*- -*
;*- Uses ACCa -*
;*- -*
;*- Performs 2's complement conversion on ACCa -*
;*--------------------------------------------------------------------------*
;****************************************************************************
compA
comf ACCaLO ;invert all bits in accumulator a
comf ACCaMID
comf ACCaHI
incf ACCaLO ;add one to accumulator a
btfsc STATUS,Z
incf ACCaMID
btfsc STATUS,Z
incf ACCaHI
retlw 0
;____________________________________________________________________________
END
pic16c622-ile-direnc-kapasitor-olcumu-rc-metre
Şifre-Pass: 320volt.com
Yayım tarihi: 2010/02/16 Etiketler: Assembly, microchip pic projeleri, pic16c622, rc metre, Visual Basic